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authorMartin Hundebøll <martin@geanix.com>2019-07-10 22:26:55 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-09-04 13:43:43 +0300
commit43a9e710cbed16e1e811713b5ccae5293471287e (patch)
tree18acd7674378d6f87973fa5721bf2e3490eb40b0 /drivers/tty/n_gsm.c
parenta64d19aa0ef62c7238e45d3f1cac90dd1915e560 (diff)
downloadlinux-43a9e710cbed16e1e811713b5ccae5293471287e.tar.xz
tty: n_gsm: add helpers to convert mux-num to/from tty-base
Make it obvious how the gsm mux number relates to the virtual tty lines by using helper functions instead of shifting 6 bits. Signed-off-by: Martin Hundebøll <martin@geanix.com> Link: https://lore.kernel.org/r/20190710192656.60381-3-martin@geanix.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/n_gsm.c')
-rw-r--r--drivers/tty/n_gsm.c19
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index c4e16b31f9ab..a60be591f1fc 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2171,6 +2171,16 @@ static inline void mux_put(struct gsm_mux *gsm)
kref_put(&gsm->ref, gsm_free_muxr);
}
+static inline unsigned int mux_num_to_base(struct gsm_mux *gsm)
+{
+ return gsm->num * NUM_DLCI;
+}
+
+static inline unsigned int mux_line_to_num(unsigned int line)
+{
+ return line / NUM_DLCI;
+}
+
/**
* gsm_alloc_mux - allocate a mux
*
@@ -2351,7 +2361,8 @@ static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len)
static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
{
- int ret, i, base;
+ unsigned int base;
+ int ret, i;
gsm->tty = tty_kref_get(tty);
gsm->output = gsmld_output;
@@ -2361,7 +2372,7 @@ static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
else {
/* Don't register device 0 - this is the control channel and not
a usable tty interface */
- base = gsm->num << 6; /* Base for this MUX */
+ base = mux_num_to_base(gsm); /* Base for this MUX */
for (i = 1; i < NUM_DLCI; i++)
tty_register_device(gsm_tty_driver, base + i, NULL);
}
@@ -2379,8 +2390,8 @@ static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
{
+ unsigned int base = mux_num_to_base(gsm); /* Base for this MUX */
int i;
- int base = gsm->num << 6; /* Base for this MUX */
WARN_ON(tty != gsm->tty);
for (i = 1; i < NUM_DLCI; i++)
@@ -2908,7 +2919,7 @@ static int gsmtty_install(struct tty_driver *driver, struct tty_struct *tty)
struct gsm_mux *gsm;
struct gsm_dlci *dlci;
unsigned int line = tty->index;
- unsigned int mux = line >> 6;
+ unsigned int mux = mux_line_to_num(line);
bool alloc = false;
int ret;